Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Women offered screening mammography experience a higher rate of diagnosis of
invasive breast cancer, without a corresponding reduction in subsequent
symptomatic breast cancer.OR in other words,
Many screen-detected invasive cancers would not have grown.
Jayant S Vaidya
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Screening mammography aims to detect breast cancer at an earlier more “curable” stage.
Therefore, in the years immediately after screening , the women who have been screened should enjoy a lower incidence of breast cancer.
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Data source:
www.isdscotland.org
These graphs are plotted in a rather unusual way
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
In Scotland, some regions are attended by a screening van for 1 year every 3 years, with no screening occurring in the interim 2 years.
For example, in the regions of Borders, Fife and Forth valley, the screening van –visits every 3 years from 1990, 1991 and 1992, respectively. In Fife, the screening year corresponds most closely to the calendar year
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Fife
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Fife
Incidence is higher in the screening year because of detection of “earlier” cancers
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
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20.0
40.0
60.0
80.0
100.0
120.0
140.0
160.0
180.0
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
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Breast Cancer incidence : age standardised rate But the incidence in the interim years is not lowered (compared with that before screening started) Despite the “earlier” detection of cancers in the screening year –the “later” cancers are not
Invasive breast cancer incidence in Fife
Incidence is higher in the screening year because of detection of “earlier” cancers
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Borders Incidence is higher in the screening year because of detection of “earlier” cancers
But the incidence in the interim years is not lowered (compared with that before screening started) Despite the “earlier” detection of cancers in the screening year –the “later” cancers are not reduced
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Forth valleyIncidence is higher in the screening year because of detection of “earlier” cancers
But the incidence in the interim years is not lowered (compared with that before screening started) Despite the “earlier” detection of cancers in the screening year –the “later” cancers are not reduced
Breast Cancer incidence : age standardised rate
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
25-29
35-39
45-49
65-69
75-79
85+
Each line represents a single cohort of women
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
45-4950-55
65-69
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
45-49
65-69
35-39
25-29
55-59
65-69
85+
75-79
55-59
45-49
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
25-29
35-39
45-49
35-39
45-4945-49
Incidence of breast cancer in those too young to have screening has remained constant
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
65-6965-69
Incidence of breast cancer in those too old to have screening has remained constant –this group (light brown line) probably had one round of screening
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
65-69
25-29
65-69
85+
55-59
This group had the benefit of the whole package of screening for 5 rounds over 15 years
45-49
35-39
45-49
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
65-69
25-29
65-69
85+
55-59
Screening stopped when they reached the age group of 65-69 between 2001 to 2003
Screening stopped
45-49
35-39
45-49
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Invasive breast cancer incidence in Scotland
65-69
45-49
65-69
35-39
25-29
65-69
85+
55-59
45-49
In 2004, despite NOT screening, the incidence remains high – and much higher than that 20, or 10 years ago
Screening stopped
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
Women who undergo regular screening mammography raise their incidence of invasive breast cancer by 30% to 60%.
In the years between consecutive screens, the incidence is not correspondingly reduced.
And, after stopping screening, rather than enjoying a reduced incidence, these women continue to experience a higher risk of invasive breast cancer
Conclusion
Data source: http://www.isdscotland.org/isd/servlet/FileBuffer?namedFile=cancer_breast_inc.xls&pContentDispositionType=inline Concept, design, analysis and graphs by Jayant S Vaidya. Submitted for publication. Confidential and not for citation
These data demonstrate the dormancy of invasive breast cancer very elegantly, in the real world.
It suggests that a much higher (up to a third) than currently believed proportion invasive breast cancers detected by screening mammography would not have grown .
Further research should focus on studying how so many women manage to keep their invasive cancers in a state of dormancy
Conclusion